A British legislator in Cameron’s government has lost a key post and is under probe for celebrating at a Nazi costume stag party.

Conservative party Member of Parliament Aidan Burley was photographed next to a Nazi-uniformed bachelor at a stag party where guests raised their glasses to toast the third Reich. Burely was wearing regular clothes but is suspected of having hired the Nazi uniform.

The government fired him as an aide to the Transport Secretary, a position that is considered a step towards becoming a minister. He retains his seat in the Parliament, but Prime Minister David Cameron has placed him under investigation

Burley later said he has “deep regret” for “inappropriate” actions at a French Alpine ski resort. The stag party, held before a bachelor gets married, featured the bachelor in an SS uniform.

“What was happening was wrong and I should have completely dissociated myself from it. I had a choice, and I made the wrong choice not to leave. I apologize for this error of judgment,” Burley wrote to the London Jewish Chronicle.

The London Daily Mail headlined its editorial on the affair, “Aidan Burley MP is an idiot,” adding that the old guard of Conservative legislators “may not have known an iPod from an earplug, but they could be trusted never to attend a Nazi-themed stag party.”